Production of diphthaloyl anthraquinones



Patented Mar. 26, 1929.

UNITED sT TEs PATENT OFFICE-1.

ARTHUR m'imrmnenans,

SHAFEN-ON-THE-RHINE,

PORATION OF DELAWARE.

ogpiunnnnnnvr, HEINRICH ismnnsrrmmnn, or mmwre- Annnnns JOSEF EMMER, or srenons TO GBA'SSELLI nrns'rnrrpggprona'rron, or NEW Y MANNHEIM, GERMANY, AS- on x; n. Y., A con- PRODUCTION or DIPHTHAIJOYL ANTHRAQUINONES.

No Drawing. Application filed September 21, 1927, Serial It is already known that'isodibenzanthrones are converted into hydroxyl derivatives of the isodibenzanthrone series, which derivatives may be used as vat dyestuffs or intermediate products for other vat dyestuifs,

by treatment with oxidizing agents. Manganese dioxid in concentrated sulfuric acid or nitric acid have hitherto been'used as oxidizing agents for this reaction.

We have now foundthat entirely new products are hydroxyl derivatives of isodibenzanthrones, and which do not show the characteristic properties of vat dyestuffs, if isodibenzanthrone or its substitution products are subjected to an energetic oxidation with particularly strong oxidizing agents, such as chromic acid, or chromic acid salts in acid '10 different solution. Considering the chemical properties and the analyses of the new oxidation products, it results that they are probably diphthaloyl anthraquinones. These products give orange-red vats with alkaline hydrosulfite solution, but have no "aflinity to vegetable. fibres.

' be employed for stuffs.

'The following example will further illustrate the nature of this invention, and how the said invention may be carried out in practice, but it is understood that the invention is not limited thereto. The parts are by weight.

the production of vat dye- E wample.

A solution of parts of isodibenzanthrone in 200 parts of sulfuric acid of 66 B. strength is introduced into a solution of 100 parts of commercial potassium bichromate in 600 parts of sulfuric acid of about cent strength in the course of two hours while stirring, the temperature being maintained at80 to 100 (3., preferably jat85 to 95 C. Stirring is. continued until a test portion of the oxidation product no longer gives a blue vat with warm alkaline hydrosulfite solution, but'gives a pure orangeobtained, which are not The new compounds may per at this temperature No. 221,137,-an d in Germany September 29, 1926.

red vat. The reaction probably proceeds according to the following equation 400a zmo The mixture is then poured into water", and the reaction product filtered off by suction.

The product is further sodium carbonate solution,

treated with warm 1n orderto extract the soluble by-products, and then worked up in the usual way.

I By recrystallizing fr brownish-yellow substance is the dried crude product concentrated sulfuric acid giving green colom nitrobenzene, a

obtained from' which dissolves in orations, /and which gives an orange-red vat, which however has no 'afiinity to vegetable fibres, with alkaline hydrosu-llite solution at room temperature.

If the chlorinated iso talnable according to dibenzanthrone, ob-

Examples 1 .and 2 of the U. S. Patent No. 1,003,268, be treated in the same manner, a reaction product having similar properties contains chlorine. In

is obtained, which a llke manner, a

diehlor-diphthaloyl-anthraquinone with similar chemical properties is obtained'from 6.6- dichlor-isodibenzant What we claim is: 1. The process of pro hrone.

ducing new anthraquinone derivatives, which consists in subj eating an isodibenzanthrone to energetic oxidation'withchromic acid.

2. The process of producing a new anthraquinone derivative, which consists in adding a sulfuric acid iso-dibenzanthrone solution to a mixture of chromic acid and sulfuric acid at temperatures of from 80 to 100 C. and completing the oxidation by further heating to about said temperature.

3. As new articles of manufacture, the new anthraquinone derivatives, which are probably diphthaloyl-anthraquinones, are employable for the production of vat dyestuffs, give orange red vats with alkaline hydrosulfite solution, which have no aflinity to vegetable fibres, and which are obtainable by sub:

jecting an isodibenzanthrone to energetic oxi-- .lution but which has no affinity to the vegetable fibre, and which is obtainable by subjecting isodibenzanthrone to energetic oxidation with chromic acid and sulfuric acid, at

ten'lperatures of from 80 to 100 C.

- In testimony whereof we have hereunto set our hands.

ARTHUR LUTTRINGHAUS. HEINRICH NERESHEIMER. HANS J OSEF EMMER. 

